I disagree completely. Spider-man 3 kinda craped on the series hard enough to kill it. Most importantly every character was ruined except maybe for aunt May as all her dialogue was golden. That time where she tells Peter about how his uncle Ben proposed to her was beautiful. Anyways here's how EVERY single character was ruined...

Peter - He eventually becomes Emo Peter (haha, no, really).

Mary Jane - Right off the bat they seem happy & like finally they're getting somewhere, but Pete's random douchey-ness to kiss a girl (Gwen of all people!) in front of Mj causing friction between then (& not the good kind). Also MJ became a random psycho b*tch after 1 bad review of her stage singing thing all of which leads their relationship back to SM2 stages. Long story short by the end they sorta reconcile but we're literally right back how we started the movie. We're getting together after so much crap!!! I lost interest in their relationship past 3.

Harry - Was set up perfectly. The way he saw Spidey over his father corpse. Wanting revenge & obsessing over it was great to see. Felt right. When he finally does appear what is he wearing? A paintball mask... This WAS VEEEERY important. He uses his father's gear as a way of sorta finally following in his father's footsteps. After being a dumb, lazy, embarrassment all of his life he's finally embracing who his father was and stepping into his shoes (literally). Instead he wore a paintball mask, wielded a katana, and his glider looked like a friggin snowboard!! Also he dies the most cliche death in the books. "Would the make-up conversation between Peter & Harry be interesting? No let's just kill Harry! After all someone the audience cares about has to die"

Gwen - Plot device. That's all she was.

Eddie/Venom - Eddie wasn't built up and was actually kinda pushed into villainy by emo Peter. He felt mostly angry & bitter at the loss of his entire life! Then he just died. The second villain in this movie to die not because they were pure evil but because they were pushed to corner and tried to fight their way out.

Sandman - The real & only villain in this flick. The guy killed uncle Ben, who would've killed MJ, and every cop in New York. The guy who brought poor old Eddie into the finally battle dooming him & Harry. And what happens? He's forgiven and flies off into the f**king sunset!!! OMFG!!!! All in the name of a daughter who doesn't even look THAT sick.

The last scene with MJ & Pete just kinda added crap to the lemon juice covered wound.